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Dynamic life cycle assessment of building systems regarding cumulative radiative forcing (ΔF) and global mean temperature change (ΔT) shows more physical and realistic results compared to usual static approaches. These dynamic metrics are especially relevant for such long-lived products. Three types of structures are assessed: steel beams, concrete beams and floors and timber beams structures. Impacts on climate change (CC) are plotted on a yearly basis depending on emission timings as well as kinetics of physical phenomena such as concrete carbonation, biogenic greenhouse gas uptakes and emissions. Steel structure shows the highest CC impact regardless of the timescale: it’s a net GHGs emitter during the fabrication stage. Concrete emits a lot at the production stage. Carbonation, which is significant only at the end-of-life once concrete is crushed, partially reduces the impact. Since wood stores a large amount of carbon at the outset under sustainable practice conditions, wooden structure has a negative contribution throughout the use phase. Temporary stored carbon is partly emitted at the end-oflife, meaning climate neutrality is achieved only under specific assumptions.

Insulating building envelope is an efficient way to increase building energy efficiency and minimize greenhouse gas emissions related to heating. After building refurbishment, on-site measurements are suitable for verifying the actual thermal transmission properties of plane building components. For instance, the standard ISO 9869-1 describes a HFM method based on the measurement of surface heat flux with heat flow sensor (HFS). This method has been extensively investigated in the literature and successfully applied on vapor tight building walls. Nevertheless, hygroscopic building insulation materials (like biobased materials) are increasingly used, and heat transfer are coupled to moisture transfer within the wall. In this case, the HFS acts as a vapor barrier: it modifies the local moisture transfer and the associated latent heat flux. In this view, this study aims to clarify what it is measured with HFS in presence of moisture transfer. The question is first treated by numerical simulation of heat and moisture transfer within hygroscopic building wall. Then, experiments are carried out on hygroscopic building insulation where the moisture effects are exaggerated.

Coronavirus disease 2019 (COVID-19) is associated with extreme inflammatory response, disordered hemostasis and high thrombotic risk. A high incidence of thromboembolic events has been reported despite thromboprophylaxis, raising the question of a more effective anticoagulation. First-line hemostasis tests such as activated partial thromboplastin time, prothrombin time, fibrinogen and D-dimers are proposed for assessing thrombotic risk and monitoring hemostasis, but are vulnerable to many drawbacks affecting their reliability and clinical relevance. Specialized hemostasis-related tests (soluble fibrin complexes, tests assessing fibrinolytic capacity, viscoelastic tests, thrombin generation) may have an interest to assess the thrombotic risk associated with COVID-19. Another challenge for the hemostasis laboratory is the monitoring of heparin treatment, especially unfractionated heparin in the setting of an extreme inflammatory response. This review aimed at evaluating the role of hemostasis tests in the management of COVID-19 and discussing their main limitations.

Small carbon budget to stay under +2°C compared to preindustrial time imply strong reduction of both embodied and operating greenhouse gases (GHGs) emissions of the building sector. This study assesses insulating materials, heating systems and their combination through two dynamic metrics – cumulative radiative forcing (ΔF) and global mean temperature change (ΔT) – applied to major well-mixed GHGs. Dynamic climate metrics better assess impacts by differentiating pulse timing and GHGs contribution over time, especially for long-lasting and biogenic products. To push them forward in LCA of products, adapted characterization factors are proposed and interpreted. With a long-term ΔT perspective, a change of heating system in the French context can mitigate warming up to 4.4±1.4 10-14 °C per m2 of insulated wall. Likewise, insulating material change leads up to ΔTlong-term=-2.09±0.45 10-14 °C per m2 of insulation that fits passive standards. Four studied insulating materials show negative ΔTlong-term. Interestingly, landfill of bio-based insulations shows higher ΔTpeak but more long-term climate benefits. By order of importance technical parameters to consider are 1) fuel and heating system type, 2) insulation thickness and 3) insulating material nature. On the whole, it is possible to have a system that provides thermal comfort while temporally showing negative temperature change, but hardly long-term climate neutrality. Lastly, broadening the number of parameters with climate zones, people’s behaviour or frugal design of living spaces, implies more consistent and effective mitigation policies.

Cement-based materials typically exhibit low tensile strength and their behaviour is generally brittle. Fibres can be added to make composites with enhanced tensile response and toughness. This study focuses on the effects of flax fibre content, mix design and processing on the hardened product properties (density, fibre orientation, surface quality, compressive and tensile strength). Effects of fibre addition on the mechanical performance of cast and extruded flax fibre reinforced composites are compared. Microstructure observations are used to study the influence of processing on fibre–matrix bond, fibre dispersion and fibre orientation. Flax fibre dispersion and orientation are also investigated to understand their effect on mechanical behaviour. In the case of cast materials, fibres do not significantly improve the mechanical behaviour. In contrast, improvement of fibre dispersion and fibre/matrix bond quality due to an extrusion process enhances mechanical performance.

Due to its low environmental impact, earth construction has received lot of consideration in recent years. Furthermore, in order to improve the quality of earth construction, there is a need for a better description and control of the earth consistency or rheology. Just as for concrete with the Abrams cone, there is need for a simple and robust test that is able to provide, under field conditions, the consistency of the earth and that has results that can be used to estimate the yield stress of a fine soil used for cob or adobe. Two types of field-oriented tests are optimized for field conditions: the first one is based on the cone penetration test as used for the determination of the Atterberg limits and the second one is the ball dropping test already used onsite to check the adequacy between the earth consistency and the construction process. Finally, an experimental validation carried out on two types of soil shows that the yield stresses computed from the field-oriented tests is in agreement with the yield stresses obtained in a conventional way using a vane rheometer.

The structural build-up of rigid fiber reinforced cement-based materials is studied. It has recently been shown that the behaviour of fiber reinforced concrete depends on the orientation of the fibers that has to be optimized during casting. As a result, there is a great interest to study the rheology of fiber reinforced concrete. One of the most important characteristics of modern fresh concretes is the structural build-up which is involved in many recent issues of concrete casting. This characteristic depends on the cement pastes chemical activity. This present work shows that structural build-up modelling used for common concretes can be generalized to fiber reinforced concretes. It can be shown that, if the inclusions percolation threshold is not reached, the structural build-up rate A thix is amplified by the addition of fibers and aggregates. Finally, this amplification of the structuration is estimated using modelling initially developed for spherical inclusions and aggregates.

Donor PTX3 polymorphisms were shown to influence the risk of invasive aspergillosis among hematopoietic stem cell transplant recipients. Here, we show that PTX3 polymorphisms are independent risk factors for invasive mold infections among 1101 solid organ transplant recipients, thereby strengthening their role in mold infection pathogenesis and patients' risk stratification.

In this work, ternary mixes of sand, cement and kaolin are studied in order to design extruded building products with reduced environmental impact. Firstly, the amount of water required to reach the extrusion rheological criterion and the immersed mechanical strength are studied. Results lead to a compressive strength prediction tool (derived from Feret model) which provides the compressive strength of a given ternary mix. Then, the dimensional and immersion stabilities of ternary mixes are studied. It shows that for mixes containing more kaolin volume than cement volume, mechanical strength is largely influenced by the saturation state. Finally, collected data show that cement stabilized clay blocks and high content cement substitution concrete can be designed with clay/cement mixes.